Wideband Code Division Multiple Access (WCDMA) mobile wireless systems have enjoyed widespread uptake of high-quality circuit-switched applications like voice and video telephony. However, they have yet to deliver to the vision of a truly ubiquitous mobile data primarily due to the absence of an efficient high-speed-packet-switched data transmission platform. Data services like mobile Internet access require asymmetric packet switched networks to best utilize the available spectrum in a multiuser environment.
High-speed downlink packet access (HSDPA) is a packet-based data service in W-CDMA downlink with theoretical peak data rates of up to 14.4 Mbps or higher by utilizing adaptive modulation and coding (AMC), hybrid ARQ (HARQ), and fast MAC scheduling. HSDPA offers high-speed downlink shared channel (HS-DSCH) that carries control information of the associated HSDPA data channel. The HS-DSCH is a mechanism to enable sharing of the HSDPA channel among multiple users. Using these channels, HSDPA systems may provide excellent packet-switched data services to several users simultaneously and efficiently.
To implement the HSDPA feature, three new physical channels, High Speed physical Downlink-Shared Channel (HS-PDSCH), High-speed Shared Control Channel (HS-SCCH), and Uplink High-Speed Dedicated Physical Control Channel (HS-DPCCH), are introduced in the physical layer specifications to enable HS-DSCH transmission. The HS-SCCH is a downlink control channel that is utilized to inform mobile devices, also called user equipment, when HSDPA data carried over the HS-PDSCH is scheduled for them, and how they may receive and decode the HSDPA data. Up to four HS-SCCH may be observed for each mobile device. The mobile devices needs to decode the HS-SCCH that carries control information such as modulation scheme, number of physical channels, transport block format, and HARQ information, for HS-PDSCH before it gets decoded on the HS-PDSCH. The HS-DPCCH is an uplink control channel used by the mobile devices to report the downlink channel quality and/or request packet retransmissions to the network.
Further limitations and disadvantages of conventional and traditional approaches will become apparent to one of skill in the art, through comparison of such systems with some aspects of the present invention as set forth in the remainder of the present application with reference to the drawings.